Introduction to Tor
and The Tor Software Ecosystem
Sukhbir Singh [email protected]
August 9, 2017 Anonymity on the Internet
2 / 29 Anonymity on the Internet
2 / 29 Anonymity on the Internet
2 / 29 Anonymity on the Internet
2 / 29 Anonymity on the Internet
2 / 29 Anonymity on the Internet
2 / 29 Anonymity on the Internet
Anonymity
2 / 29 Anonymity on the Internet
2 / 29 “On the Internet, Nobody Knows...”
†
† Image from The New Yorker cartoon by Peter Steiner, 1993 3 / 29 On the Internet, They Know...
4 / 29 Tor: The Onion Router
5 / 29 Tor: The Onion Router
Client
Destination
5 / 29 Tor: The Onion Router
Client
Destination
5 / 29 Tor: The Onion Router
Client
Destination
5 / 29 Tor: The Onion Router
Entry Guard (I) Client
Middle Relay (II) Exit Relay (III) Destination
5 / 29 Tor: The Onion Router
Entry Guard (I) Client
Entry Middle Exit
Middle Relay (II) Exit Relay (III) Destination
5 / 29 Tor: The Onion Router
✓Source [IP] × Destination [Resource]
Entry Guard (I) Client
Middle Relay (II) Exit Relay (III) Destination
5 / 29 Tor: The Onion Router
Entry Guard (I) Client
Middle Relay (II) Exit Relay (III) Destination
× Source [IP] ✓Destination [Resource]
5 / 29 I Distributed design
I 2,000,000 users and 6000 relays
I 100 Gbit/sec available bandwidth
Tor: The Onion Router
I Low-latency anonymity
∗https://metrics.torproject.org 6 / 29 I 2,000,000 users and 6000 relays
I 100 Gbit/sec available bandwidth
Tor: The Onion Router
I Low-latency anonymity
I Distributed design
∗https://metrics.torproject.org 6 / 29 Tor: The Onion Router
I Low-latency anonymity
I Distributed design
I 2,000,000 users and 6000 relays
I 100 Gbit/sec available bandwidth
∗https://metrics.torproject.org 6 / 29 I Journalists
I Activists
I You...
Who Uses Tor?
7 / 29 I Activists
I You...
Who Uses Tor?
I Journalists
7 / 29 I You...
Who Uses Tor?
I Journalists
I Activists
7 / 29 Who Uses Tor?
I Journalists
I Activists
I You...
7 / 29 Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + + Anonymity + ++ +++ Privacy − + +++ Speed ++ −− −− Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Appear Elsewhere ++ + + Anonymity + ++ +++ Privacy − + +++ Speed ++ −− −− Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Anonymity + ++ +++ Privacy − + +++ Speed ++ −− −− Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + +
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Privacy − + +++ Speed ++ −− −− Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + + Anonymity + ++ +++
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Speed ++ −− −− Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + + Anonymity + ++ +++ Privacy − + +++
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Cost −− +++ +++
Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + + Anonymity + ++ +++ Privacy − + +++ Speed ++ −− −−
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 Tor vs. VPN
† VPN Tor Tor Browser Censorship Evasion ++ +++ +++ Appear Elsewhere ++ + + Anonymity + ++ +++ Privacy − + +++ Speed ++ −− −− Cost −− +++ +++
† Modified under CC BY-SA 4.0. Original work by Tim Sammut from https://teamsammut.com/blog/2015/08/tor-vs-vpn-and-proxies-slides.html 8 / 29 † I Runs as a daemon and sets up a local SOCKS5 proxy
I Platform support: Linux, macOS, Windows, BSD variants
little-t-tor
I Core of the Tor software ecosystem
†localhost:9050 9 / 29 I Platform support: Linux, macOS, Windows, BSD variants
little-t-tor
I Core of the Tor software ecosystem
† I Runs as a daemon and sets up a local SOCKS5 proxy
†localhost:9050 9 / 29 little-t-tor
I Core of the Tor software ecosystem
† I Runs as a daemon and sets up a local SOCKS5 proxy
I Platform support: Linux, macOS, Windows, BSD variants
†localhost:9050 9 / 29 Tor Browser
Tor Browser (Bundle) https://www.torproject.org/torbrowser
10 / 29 Onion Services
Onion Service
11 / 29 Onion Services
Onion Service
11 / 29 Onion Services
Onion Service
11 / 29 Onion Services
Onion Service
11 / 29 Tor Software Ecosystem
Tor is not just Tor Browser!
12 / 29 HTTPS Everywhere
Browser Extension for Enabling HTTPS https://www.eff.org/https-everywhere
13 / 29 Orbot and Orfox
Tor and Tor Browser on Android https://guardianproject.info/
14 / 29 Tails
Secure Operating System https://tails.boum.org/
15 / 29 torsocks
$ . torsocks on
Wrapper to Torify Applications https://gitweb.torproject.org/torsocks.git
16 / 29 Ricochet
Anonymous P2P Instant Messaging Client https://ricochet.im/
17 / 29 Tor Messenger
Chat Client with native Tor and OTR Support https://trac.torproject.org/projects/tor/wiki/doc/TorMessenger
18 / 29 TorBirdy
Thunderbird Extension for Secure Email Communication https://trac.torproject.org/projects/tor/wiki/torbirdy
19 / 29 Pluggable Transports
Obfuscate Tor Traffic https://www.torproject.org/docs/pluggable-transports.html.en
20 / 29 Metrics
Directly connecting users
2 500 000
2 000 000
1 500 000
1 000 000
500 000
0
Jun−2017 Jul−2017 Aug−2017
The Tor Project − https://metrics.torproject.org/
Tor Network Metrics https://metrics.torproject.org/
21 / 29 Stem
Python Controller https://stem.torproject.org/
22 / 29 Nyx
Tor CLI Monitor https://nyx.torproject.org/
23 / 29 txtorcon
Twisted-based Python Asynchronous Controller https://github.com/meejah/txtorcon
24 / 29 OONI
Open Observatory of Network Interference https://ooni.torproject.org/
25 / 29 Check
Test Your Network Settings https://check.torproject.org/
26 / 29 SecureDrop
Open-source Whistleblower Submission System https://securedrop.org/
27 / 29 GetTor
torproject.org blocked?
Provides Alternative Access to Tor Project Software https://gettor.torproject.org/
28 / 29 Thank You
Come hack with us! https://www.torproject.org/getinvolved/
E4AC D397 5427 A5BA 8450 A1BE B01C 8B00 6DA7 7FAA
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